Westpac Chief Executive Officer, Gail Kelly, unveiled the new structure which splits the business into two units, Australian Financial Services - encompassing the group's retail and business banking units, products and risk management operations - and Group Services, which swallows up technology, banking operations, property services and legal.

The AFS unit will be led by Brian Hartzer, who joins the group from RBS in 2012. In addition, Peter Clare, group executive, product & operations, will be moving to the new role of chief operating officer, AFS. His responsibilities will include product management and development, risk management, management of customer contact centres, and online and mobile banking.

Group Services will be led by John Arthur who will become the Westpac Group's COO. McKinnon, who has overseen the rebuilding of technology capability at Westpac, has decided "to step back from a full-time group executive role" says the bank. Instead, he will take on a 'senior oversight' position, reporting into Arthur.

Says Kelly: "In John and Bob, we have two seasoned executives each with a record of delivering strong commercial outcomes. Over the past three years they have worked closely together on a wide range of critical projects including IT transformation, merger integration, our Strategic Investment Priorities portfolio and more recently our new sourcing plans."

The changes in technology reporting lines are broadly similar to those introduced by rival bank ANZ last month, which saw CIO Ann Weatherston stripped of her direct line to chief executive Mike Smith following the appointment of a new chief operating officer Alistair Currie.